operater ovrld unary r.i.p

#include<iostream.h>

class ovrld
{
public:
    int x;
    void display();
    void operator-()
    {
        x=-x;
    }
};

void ovrld::display()
{
    cout<<"the integer value is:\n"<<x<<endl;
}

int main()
{
    ovrld s;
    cout<<"enter a integer value to negate it\n";
    cin>>s.x;
    cout<<"value before negation is:\n";
    s.display();
    -s;
    cout<<"value after negation is:\n";
    s.display();
    return 0;
}

OUTPUT:
enter a integer value to negate it
3
value before negation is:
the integer value is:
3
value after negation is:
the integer value is:
-3
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